无线信道中OFDM技术和QAM技术传输的性能差异

The Difference between OFDM Technique and QAM Technique in Wireless Communication Systems

本文介绍了OFDM技术。OFDM是一种多载波调制技术,能够把有符号间干扰的信道转换成无符号间干扰的并行子信道,所以,OFDM技术能够有效的对抗信道的频率选择性衰落,它已经得到了广泛的应用。本文比较了语音文件在OFDM系统和QAM系统中的传输效果,得出在相同条件下OFDM调制要优于QAM调制的结论。

The paper introduces OFDM technique. OFDM converts an intersymbol interference （ISI） channel into parallel ISI-free subchannels, so OFDM scheme is robust to frequency-selective fading and is used widely. Simulations illustrate the superiority of OFDM technique over competing QAM alternatives in the presence of wireless channels. It concludes that OFDM outperforms QAM under the same channel condition by comparing the transmitting effects of voice.